The document discusses the author's experience optimizing code for a MUD (multi-user dungeon) game written in Perl. It describes rewriting the MUD several times using different languages and frameworks to improve performance. Key optimizations included rewriting color encoding functions in pure Perl, C using Inline::C, and applying techniques like unrolling loops. Benchmarking showed the C version using Inline::C provided the best 10x performance gain over the original pure Perl implementation.

1. MUD on speed Marco Fontani – Glasgow.pm - 2011-05-12

2. MUD on speed A journey I failed to talk about yet, about Perl, MUDs, strings, Gentoos, and other funny characters. And some who think they are funny.

4. ~20 italian users logged in most evenings

5. V2, rewrite - still in C

6. V3, attempted rewrite in C++ merging code from another developer who joined

7. Came to Scotland.. no v4 for a while.

9. speed/workflow fake user tests

10. Handled ~20/30 (fake) users constantly submitting output-intensive commands (admittedy with zlib compression)

11. A select loop in 1999 handled more

13. speed/workflow fake user tests

14. Now handles a hell of a lot of users, asynchronously, making db connections, using background tasks, etc.

15. But let's not get ahead of ourselves

25. That's all folks!

27. That's all folks!

29. Use (faster) tr

30. Use (much faster) array lookups

31. Use $_[0] for speed

32. Use map, join and quotemeta

33. -funroll-loops the Inline::C version (that was me!)

38. It's in CORE

39. It's designed for helping with similar problems

40. It usually works

42. Rate Memoized Pure Perl Pure Perl

43. Memoized Pure Perl 15012/s -- -54%

44. Pure Perl 32573/s 117% --